Instead of gold, would it be more accurate for the monkey king’s cloud to be purple? 13th century and zaju play as examples before the final version. Unless the cloud is described specifically as gold in the final I don’t remember
I don't believe the 13th-century JTTW mentions the color. I'm not sure about zaju.
The standard 1592 edition sometimes describes Monkey's cloud as “auspicious" (xiangyun, 祥雲) or having a "luminosity" (xiangguang, 祥光). Such clouds/lights are commonly associated with the five colors (wuse, 五色). Chapter 88 makes this explicit:
Marvelous Great Sage! With a loud whistle he somersaulted right up into midair, his two feet treading the auspicious cloud of five colors. At about three hundred paces above ground, he let loose his rod to make [the martial arts moves] Sprinkling Flowers over the Top and the Yellow Dragon Entwining the Body. Up and down he moved, circling left and right. In the beginning his person and the rod so complemented each other that they seemed, as the adage had it, like flowers added to brocade. By and by even the person disappeared, and all one could see was a sky full of twirling rods! (Wu & Yu, 2012, vol. 4, pp. 196-197) 好大聖，唿哨一聲，將觔斗一抖，兩隻腳踏著五色祥雲，起在半空，離地約有三百步高下。把金箍棒丟開個「撒花蓋頂」，「黃龍轉身」，一上一下，左旋右轉，起初時人與棒似錦上添花；次後來不見人，只見一天棒滾。
Source:
Wu, C., & Yu, A. C. (2012). The Journey to the West (Vols. 1-4) (Rev. ed.). Chicago, Illinois: University of Chicago Press.
